Electric appliances, e.g., electric shavers and electric toothbrushes, having electric motors for driving oscillatory motor components are known in the art. For example, a device of this type is described in DE 1 151 307 A, which discloses an oscillating armature drive for a dry shaving apparatus. The oscillating armature drive includes a reciprocating shaving cutter and a U-shaped electromagnet formed fast with a housing of the shaving apparatus. A working armature and compensating armatures, adjacent the working armature on opposite sides, are arranged near the poles of the electromagnet. In operation, the working armature, which drives the shaving cutter, oscillates parallel to the pole faces of the electromagnet, and the compensating armatures oscillate in phase opposition to the working armature to prevent the transmission of oscillations from the working armature to the housing of the shaving apparatus.
As another example, DE 196 80 506 T1 discloses an electric shaving apparatus having a linear oscillation motor with a stationary electromagnet and a plurality of movable components that are set in oscillatory motion in phase opposition to each other by the electromagnet. The movable components are interconnected by a linkage mechanism that transfers the oscillatory motion from one movable component to another with simultaneous reversal of direction.
DE 197 81 664 C2 discloses an electric shaver with a linear drive that has a hollow cylindrical stator with an electromagnetic coil. Arranged in the stator are two movable elements that are driven in phase opposition to each other, the one element driving a shaving cutter while the other element may have a counterweight to suppress vibrations.
EP 1 193 844 A1 discloses a linear oscillator. A housing, constructed as a stator, accommodates a rotor that executes a reciprocating motion. A movable spindle, contained with the housing, controls the amplitude of oscillation of the rotor. The rotor and the spindle are coupled to each other and to the housing by springs. The oscillatory motion generated by the linear oscillator can be transferred to either the rotor or the spindle, thereby reducing the transmission of oscillatory motions to the housing.